The polymerization of .alpha.-monoolefins to useful thermoplastic polymers by catalysis employing coordination catalysts is well known. Generally, the coordination catalysts comprise at least two compounds, one being a compound of a transition metal of groups IV-VIII of the Periodic Table, referred to herein as "procatalyst" and the other being an organometallic compound of a metal of groups I-III of the Periodic Table, referred to herein as "cocatalyst". Such coordination catalyst systems are often referred to as Ziegler catalysts. A group of these catalysts which is stereoregulating in the production of polymers of propylene and higher .alpha.-monoolefins is often referred to as Ziegler-Natta catalysts. In commercial Ziegler-Natta catalysts, the procatalyst is generally an active form of titanium chloride and the cocatalyst an alkyl- or alkyl halide compound of aluminum. These catalysts may be further modified by addition of compounds which increase the stereoregulating effect of the catalysts, referred to herein as selectivity control agents.
Polymers of ethylene, propylene, 1-butene and 4-methyl-1-pentene produced by means of such coordination catalysts are materials of commerce, both as homopolymers and copolymers.
A new alphamonoolefin polymer has now been found.